Vulcanized rubber boots and their die-casting mold, manufacturing apparatus and manufacturing method

Abstract

A die-casting mold for vulcanized rubber boots, comprising: a combined barrel mold having an inner cavity corresponding to the barrel of a rubber boot; a last mold with a separating element, having a main body substantially corresponding to the shape of the barrel of a rubber boot, and two or more separating elements provided on the main body, the last mold being adapted to be mounted into the inner cavity of the barrel mold to form a die-casting forming cavity between the wall of the inner cavity of the barrel mold and the outer surface of the last mold, the die-casting forming cavity being separated by the last mold and the barrel mold into two or more parts; and a glue guide plate adapted to be mounted on top of the barrel mold to guide the injection of unvulcanized rubber compound, comprising a plate body, wherein the plate body is provided with: a glue injection hole adapted to be connected with an external injection head to inject unvulcanized rubber compound; and an annular glue injection channel for guiding the externally injected unvulcanized rubber compound into the die-casting forming cavity in an annular distribution.

Description

Technical Field

[0001] This invention relates to a vulcanized rubber boot and its die-casting mold, manufacturing equipment, and manufacturing method. Background Technology

[0002] Vulcanized rubber boots are widely used in various industries, such as labor protection, fire fighting, fishing, outdoor sports, and fashion. They have high requirements for waterproof performance. For certain specific working environments, it may be necessary to line the inside of vulcanized rubber boots with a lining, especially a lining with foam and insulation materials.

[0003] However, unlike PVC materials, rubber has poor fluidity, making it difficult to achieve integral die casting in the current vulcanized rubber boot manufacturing industry. Semi-automated production lines dominate the industry.

[0004] In a semi-automated production line, rubber sheets of predetermined shapes and thicknesses are first manufactured through processes such as mixing, extrusion, and calendering. Workers on the assembly line then fit the boot lining onto the shoe last, and pre-made rubber sheets of various shapes are tightly adhered to the lining in a predetermined manner to form the shaft of the vulcanized rubber boot. Depending on the process, the pre-made sole can be glued to the shaft of the vulcanized rubber boot before or after vulcanization, thus completing the overall manufacturing process.

[0005] To detect air or water leaks, specialized equipment is needed to manually test the barrel section or the entire vulcanized rubber boot. Typically, because the barrel section is formed by manually stacking rubber sheets, leaks are quite common in vulcanized rubber boots manufactured in this way. Some areas are difficult to repair in subsequent processes, resulting in a high scrap rate and significantly increasing the production cost of vulcanized rubber boots.

[0006] Therefore, an improved vulcanized rubber boot manufacturing process is needed. Summary of the Invention

[0007] According to one aspect of the present invention, a die-casting mold for a vulcanized rubber boot is provided, comprising: a combined barrel mold having an inner cavity corresponding to the barrel of the rubber boot; a last mold with partition elements having a main body substantially corresponding to the shape of the barrel of the rubber boot, and two or more partition elements disposed on the main body, the last mold being adapted to be installed in the inner cavity of the barrel mold to form a die-casting cavity between the wall of the inner cavity of the barrel mold and the outer surface of the last mold, the die-casting cavity being divided into two or more parts by the last mold and the barrel mold; and an injection guide plate adapted to be installed on top of the barrel mold to guide the injection of unvulcanized compound rubber, comprising a plate body, wherein the plate body is provided with: an injection hole adapted to be connected to an external injection head to inject unvulcanized compound rubber; and an annular injection channel for guiding the externally injected unvulcanized compound rubber in an annular distribution into the die-casting cavity.

[0008] Preferably, the dividing element of the shoe last mold includes two dividing plates extending from the front and rear sides of the shoe last mold, respectively.

[0009] Preferably, when the shoe last mold is installed into the barrel mold, the two partition plates divide the die-casting cavity into a left chamber and a right chamber.

[0010] Preferably, the cylinder mold includes a left cylinder mold and a right cylinder mold that can be matched and installed together; the two partition plates separate the left chamber and the right chamber corresponding to the left cylinder mold and the right cylinder mold.

[0011] Preferably, the dividing element of the shoe last mold includes three dividing plates, the first dividing plate extending rearward from the shoe last mold, and the second and third dividing plates extending to the left and right sides of the shoe last mold, respectively.

[0012] Preferably, when the shoe last mold is installed into the barrel mold, the three partition plates divide the die-casting cavity into three chambers: the middle chamber, the left chamber, and the right chamber.

[0013] Preferably, the cylindrical mold includes three cylindrical mold parts that can be installed together; the three partition plates separate the middle chamber, left chamber and right chamber corresponding to the three cylindrical molds respectively.

[0014] Preferably, the dividing element of the shoe last mold includes a dividing plate, a left step portion and a right step portion, the dividing plate extending rearward from the shoe last mold, and the left step portion and the right step portion extending vertically on the left and right sides of the shoe last mold, respectively.

[0015] Preferably, when the shoe last mold is installed into the barrel mold, the partition plate, the left step portion, and the right step portion divide the die-casting cavity into a middle chamber, a left chamber, and a right chamber.

[0016] Preferably, the cylinder mold includes an intermediate cylinder mold, a left cylinder mold, and a right cylinder mold that can be installed together; the partition plate, the left step portion, and the right step portion separate the intermediate chamber, the left chamber, and the right chamber corresponding to the intermediate cylinder mold, the left cylinder mold, and the right cylinder mold.

[0017] Preferably, the left and right stepped portions of the shoe last mold cooperate with the left and right sides of the intermediate cylinder mold to form an intermediate cavity; the left and right cylinder molds surround the middle and rear part of the shoe last mold to cooperate with the partition to form a left cavity and a right cavity.

[0018] Preferably, the shoe last mold further includes a top step portion for sealing the upper part of the intermediate chamber.

[0019] Preferably, the shoe last mold and the intermediate cylinder mold further include a lower step portion that cooperates with each other to close the lower part of the intermediate cavity.

[0020] Preferably, the left and right barrel molds include stepped portions that mate with the last mold and the intermediate barrel mold to form closed left and right chambers.

[0021] Preferably, the left and right barrel molds cooperate to surround the middle barrel mold and the last mold.

[0022] Preferably, the inner surface of the cylindrical mold has features suitable for bonding with a rubber surface.

[0023] Preferably, it further includes: a second shoe last mold without a separator element, adapted to be installed into the inner cavity of the barrel mold.

[0024] Preferably, the second shoe last mold has a shape corresponding to the barrel of a rubber boot, so as to form a barrel forming cavity between the wall of the inner cavity of the barrel mold and the outer surface of the shoe last mold without a partition plate.

[0025] Preferably, the second shoe last mold has a shape different from the barrel shape of a rubber boot.

[0026] Preferably, the second shoe last mold has an inflation channel suitable for connecting to an external pressurized air source and an exhaust hole disposed on its surface.

[0027] Preferably, the second shoe last mold is provided with an airbag.

[0028] Preferably, the top of the cylindrical mold and the bottom of the glue injection guide plate have mating joints, and the glue injection guide plate is adapted to be molded to the top of the cylindrical mold through the mating joints.

[0029] Preferably, the die-casting mold further includes: an outsole mold having an outsole injection hole and an outsole cavity corresponding to the shape of the rubber boot sole, for die-casting the sole of the rubber boot; the outsole mold has an outsole joining part and is adapted to be molded to the top of the barrel mold and the top of the injection guide plate through the outsole joining part.

[0030] Preferably, the plate body is further provided with a distribution chamber, which is connected to the glue injection hole through the glue injection channel and to the annular glue injection channel through the guide channel.

[0031] Preferably, there are multiple flow channels, each of which connects the distribution chamber to the annular injection channel; preferably, there are four flow channels, distributed at intervals around the distribution chamber.

[0032] Preferably, the glue injection hole is located on one side of the plate, and the distribution chamber is located in the middle of the plate.

[0033] Preferably, the annular injection channel is an annular outlet formed at one end face of the plate body. More preferably, the shape formed by the annular outlet corresponds to the annular shape at the bottom of the rubber boot body.

[0034] According to another aspect of the present invention, a die-casting molding apparatus for rubber boots is provided, comprising: a die-casting mold according to the above aspects; a high-pressure injection mechanism for pressurizing and injecting a prepared unvulcanized compound into the injection hole of the die-casting mold; a mold moving mechanism for moving various parts of the die-casting mold according to a preset program; and a control mechanism for controlling the operation of the mold moving mechanism and the high-pressure injection mechanism.

[0035] Preferably, the die-casting molding equipment also includes heating equipment for heating the unvulcanized compound.

[0036] According to another aspect of the present invention, a method for manufacturing vulcanized rubber boots using die-casting equipment according to the above aspects is provided, comprising: moving a last mold with a separating element between separate barrel molds; closing the barrel mold to accommodate the last mold in a suitable position within the barrel mold; positioning and fixing an injection guide plate on the top of the barrel mold; injecting glue into the injection holes of the injection guide plate, and thereby injecting unvulcanized compounded rubber into the die-casting cavity between the barrel mold and the last mold through the annular injection channel of the injection guide plate; opening the barrel mold and removing the last mold; fitting a second last mold without a separating element onto the boot lining and moving it between the barrel molds; closing the barrel mold to accommodate the second last mold in a suitable position within the barrel mold; and vulcanizing the unvulcanized compounded rubber to form the barrel of the rubber boot.

[0037] Preferably, before vulcanizing the unvulcanized compounded rubber, the following steps are also included: closing the outsole mold onto the upper part of the injection guide plate, and injecting rubber into the outsole injection hole of the outsole mold to form the boot sole; removing the injection guide plate from the barrel mold, and closing the outsole mold with the barrel mold; injecting pressurized air into the inside of the boot lining through the air channel in the second shoe last mold to press the boot lining against the inner surface of the barrel and apply pressure to the barrel, while heating the barrel and the second shoe last mold through a heating device, so that the unvulcanized compounded rubber is vulcanized, and the barrel and the boot sole are vulcanized as a whole to form an integrated vulcanized rubber boot.

[0038] Preferably, the method further includes: placing an airbag between the boot lining and the second shoe last mold to apply pressure evenly to the boot lining.

[0039] Preferably, the method further includes: the second shoe last mold having a shape different from that of a rubber boot.

[0040] Preferably, the method further includes: removing the outsole mold after vulcanization, opening the barrel mold, and allowing the vulcanized rubber boot to exit the die-casting molding equipment together with the second shoe last mold.

[0041] Preferably, the method further includes: removing the vulcanized rubber boot from the second shoe last mold using a pneumatic device.

[0042] According to another aspect of the present invention, a one-piece vulcanized rubber boot is provided, which is die-cast using the methods according to the above aspects, including a one-piece die-cast shaft, a sole, and a boot lining.

[0043] Although embodiments of the present invention are described as being applied to die casting processes, they are equally applicable to injection molding processes; and the scope of protection of the present invention is also intended to cover such applications. Attached Figure Description

[0044] The invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, wherein similar elements are numbered in a similar manner, wherein:

[0045] Figures 1a-1d This is a schematic diagram of the glue injection guide plate according to the present invention.

[0046] Figure 2 a-2d is a schematic diagram of a die-casting mold according to an embodiment of the present invention.

[0047] Figure 3 This is another schematic diagram of the die-casting mold according to the present invention, showing the closed state of the cylinder mold.

[0048] Figure 4 This is another schematic diagram of a die-casting mold according to the present invention, showing a state in which the mold is closed.

[0049] Figure 5 This is another schematic diagram of the die-casting mold according to the present invention, showing another state of mold closing.

[0050] Figures 6a-6c This is a schematic diagram of a die-casting mold according to another embodiment of the present invention.

[0051] Figure 7 This is another schematic diagram of the die-casting mold according to the present invention, showing the closed state of the cylinder mold.

[0052] Figure 8 This is another schematic diagram of a die-casting mold according to the present invention, showing a state in which the mold is closed.

[0053] Figure 9 This is another schematic diagram of the die-casting mold according to the present invention, showing another state of mold closing.

[0054] Figure 10a and 10b This is a schematic diagram of a portion of the barrel mold of a die-casting mold according to another embodiment of the present invention.

[0055] Figure 11 This is a schematic diagram of a portion of the barrel mold of a die-casting mold according to another embodiment of the present invention.

[0056] Figures 12a-12c This is a schematic diagram of a shoe last mold with a separating element according to another embodiment of the present invention.

[0057] Figure 13 This is a schematic diagram of the cylinder mold of a die-casting mold according to another embodiment of the present invention.

[0058] Figure 14 and Figure 15 This is a schematic diagram of the mold closing mechanism according to the present invention.

[0059] Figure 16a and 16b This is a schematic diagram of a glue-injection guide plate according to another embodiment of the present invention.

[0060] Figure 17 This is a schematic diagram of the outsole mold according to another embodiment of the present invention. Detailed Implementation

[0061] The technical solution of the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings, but the present invention is not limited to the following embodiments.

[0062] To address the issue of poor flowability of rubber (e.g., uncured compound rubber) making it difficult to injection mold or die-cast rubber boots (e.g., one-piece vulcanized rubber boots), the inventors of this invention have manufactured an injection guide plate for guiding the injection of uncured compound rubber. To address the difficulty in achieving one-piece molding of vulcanized rubber boots with linings, the inventors of this invention have invented related die-casting molds, production lines, and manufacturing processes. One-piece vulcanized rubber boots produced using these devices or processes are also within the scope of this invention.

[0063] like Figures 1a-1d As shown, according to one aspect of the present invention, a sprue for guiding the injection of uncured rubber compound is provided, comprising a plate body. The plate body is generally square and made of a material suitable for manufacturing high-pressure molds.

[0064] Figure 1a The external structure of the glue injection guide plate is shown. Figure 1b A schematic diagram of the internal structure of the glue injection guide plate is shown. Figure 1c A schematic diagram of the cavity and channel of the glue injection guide plate is shown, and Figure 1d The diagram shows the interaction between the injection guide plate and other molds in the installation position.

[0065] The plate may be provided with: injection holes for connecting to an external injection head to inject unvulcanized compound; and an annular injection channel for discharging the externally injected unvulcanized compound in a annular distribution. For example... Figure 1d As shown, the uncured compounded rubber discharged from the annular injection channel is introduced into other molds, such as the mold for producing the shaft of rubber boots, which will be described in detail below.

[0066] The plate body may also be provided with a distribution chamber, which is connected to the injection hole through an injection channel and to the annular injection channel through a guide channel. The distribution chamber facilitates the smooth discharge of the uncured compound.

[0067] There can be one or more flow channels, preferably multiple, each connecting the distribution chamber to the annular injection channel. Preferably, there are four flow channels, spaced apart around the distribution chamber. Multiple flow channels facilitate smoother flow of the uncured compound from the distribution chamber to the annular channel, helping to reduce pressure.

[0068] As shown in the figure, the glue injection hole can be set on one side of the board, and the distribution chamber is set in the middle of the board.

[0069] like Figure 1a As shown, the annular injection channel is an annular outlet formed in the bottom of the plate, and the shape of the annular outlet corresponds to the annular shape of the bottom of the vulcanized rubber boot body.

[0070] In some embodiments, the annular injection channel is formed as a continuous annular outlet. In other embodiments, the annular injection channel is formed as a discontinuous annular outlet, for example, the annular injection channel has a plurality of evenly spaced circular outlets. In all these ways, the unvulcanized compound can be injected into the barrel mold in an annular or substantially annular manner.

[0071] The aforementioned guide plate can be used in conjunction with other molds (e.g., barrel mold, outsole mold) to form a die-casting mold for a vulcanized rubber boot according to another aspect of the present invention.

[0072] In general, the die-casting mold for vulcanized rubber boots according to the present invention may include: a combined barrel mold having an inner cavity corresponding to the barrel of the rubber boot; a last mold with partition elements having a main body substantially corresponding to the shape of the barrel of the rubber boot, and two or more partition elements disposed on the main body, the last mold being adapted to be installed in the inner cavity of the barrel mold to form a die-casting cavity between the wall of the inner cavity of the barrel mold and the outer surface of the last mold, the die-casting cavity being divided into two or more parts by the last mold and the barrel mold; and an injection guide plate adapted to be installed on top of the barrel mold to guide the injection of unvulcanized compound rubber, comprising a plate body, wherein the plate body is provided with: an injection hole adapted to be connected to an external injection head to inject unvulcanized compound rubber; and an annular injection channel for guiding the externally injected unvulcanized compound rubber in an annular distribution into the die-casting cavity.

[0073] Figure 2 a-2d illustrates a barrel mold, a shoe last mold, and an outsole mold that can be used with a baffle plate according to an embodiment of the present invention.

[0074] Figure 2In the embodiments shown in a-2d, the combined cylindrical mold comprises three parts: a left cylindrical mold 25, a middle cylindrical mold 26, and a right cylindrical mold 24. These cylindrical molds can be joined together to form a complete cylindrical mold. The complete cylindrical mold includes a complete cylindrical forming cavity corresponding to the cylindrical body of the rubber boot.

[0075] According to an embodiment of the present invention, two types of shoe last molds are included: a shoe last mold 27 with a separator element, and second shoe last molds 21 and 22 without a separator element.

[0076] The second shoe last mold 21 without separators represents the second shoe last mold before the boot lining is installed, and the second shoe last mold 22 without separators represents the second shoe last mold after the boot lining is installed. The boot lining can be a relatively thick boot lining, such as a textile fabric, foam material, a composite material of textile fabric and foam material, a composite material of textile fabric and insulation material, or a composite material of textile fabric, foam material, and insulation material, etc. The manufacturing method according to the invention is particularly advantageous for the one-piece manufacturing of vulcanized rubber boots with relatively thick boot linings.

[0077] The separating element of the shoe last mold 27 according to this embodiment may include three separating plates. The first separating plate extends rearward from the shoe last mold 27 with separating plates, and the second and third separating plates extend to the left and right sides of the shoe last mold 27 with separating plates, respectively. The separating element or separating plate may extend along the entire longitudinal direction (vertical direction in the figure) of the main body portion of the shoe last mold 27.

[0078] When the shoe last mold 27 with the dividing elements is installed into the barrel mold, the three dividing plates divide the die-casting cavity formed between the outer surface of the shoe last mold and the inner surface of the barrel mold into three chambers: the front chamber, the left chamber, and the right chamber.

[0079] Since the cylinder mold comprises three cylinder mold parts that can be fitted together (left cylinder mold 25, right cylinder mold 26, and rear cylinder mold 26 in the figure), the three partition plates can separate the die-casting cavity parts corresponding to the three cylinder molds respectively. That is, as Figure 3 As shown, the three partition plates of the shoe last mold 27 with partition elements are located at the junction of the three cylinder molds, thereby cooperating with each other to divide the die casting cavity into three chambers. Figure 3 The illustration shows the situation where the three shaft molds are closed and combined with the shoe last mold 27 with separator elements to form three separate chambers. The three separate chambers correspond to the shapes of corresponding parts of the rubber boot shaft, thus allowing the formation of three separate shaft sections during the die-casting process of the rubber material. The three separate shaft sections can be joined together in subsequent steps to form a complete shaft.

[0080] As described above, the die-casting mold further includes second last molds 21 and 22 without separators, adapted to be installed into the inner cavity of the boot body mold. In a preferred embodiment, the second last mold may have a shape corresponding to the boot body of the rubber boot to form a complete boot body forming cavity between the wall of the inner cavity of the boot body mold and the outer surface of the second last mold without separators. The complete boot body forming cavity corresponds to the boot body of the rubber boot. Figure 5 This illustrates the situation where the three barrel molds are closed and combined with the second last mold 21 or 22 without separator elements to form a complete barrel forming cavity.

[0081] In other embodiments, the second shoe last mold may have a shape different from the shape of the rubber boot's body. The main function of the second shoe last mold is to support the boot lining. The second shoe last mold may have an inflation channel suitable for connecting to an external pressurized air source and vent holes on its surface, which can discharge external pressurized gas from the surface, thereby pushing the boot lining to conform to the body and applying a certain pressure to the body to help the separated parts of the body engage with each other.

[0082] In a preferred embodiment, the second shoe last mold is provided with an air bladder. Since the boot lining may be breathable, leading to uneven pressure, an air bladder is placed between the boot lining and the second shoe last mold to apply pressure evenly to the boot lining and the boot shaft. This air bladder can, for example, surround the second shoe last mold.

[0083] According to the present invention, the top of the barrel mold and the bottom of the injection guide plate have matching mating portions, and the injection guide plate is adapted to be closed onto the top of the barrel mold through the mating portions. For example, Figure 1a , 1b The protrusion shown can be matched to the corresponding recessed portion on the top of the cylinder mold. Other connecting elements can also be used.

[0084] According to the present invention, the die-casting mold may further include an outsole mold 23 having an outsole injection hole and an outsole cavity corresponding to the shape of the rubber boot sole, for die-casting the sole of the rubber boot. The outsole mold 23 has an outsole joining portion and is adapted to be closed to the top of the barrel mold or the top of the injection guide plate through the outsole joining portion when needed.

[0085] For example, Figure 2 The protruding blocks around the top of the left cylindrical mold 25 and the right cylindrical mold 24, and Figure 1a The recessed parts at the bottom of the middle guide plate can match each other, so that the guide plate and the cylinder mold can be precisely positioned to each other.

[0086] Figure 3 and Figure 4The diagram shows partial and complete assembly of the outsole mold, guide plate, barrel mold, and last mold with three partitions.

[0087] According to another embodiment of the invention, for example, Figures 6a-6c As shown, the separating element of a shoe last mold with a separating element may include two separating plates extending from the front and rear sides of the shoe last mold, respectively. The separating element or separating plate may extend along the entire longitudinal direction (vertical direction in the figure) of the main body of the shoe last mold.

[0088] At this time, as Figure 6a As shown, the cylinder mold may include a left cylinder mold and a right cylinder mold that can be matched and installed with each other.

[0089] When the shoe last mold with the dividing element is installed into the barrel mold, the two dividing plates divide the die-casting cavity into two chambers.

[0090] The two partition plates separate the die-casting cavities corresponding to the left and right barrel molds. The two separate cavities correspond to the shapes of corresponding portions of the rubber boot barrel, thus allowing the formation of two separate barrel sections during the die-casting process of the rubber compound. The two separate barrel sections can be joined in subsequent steps to form a complete barrel.

[0091] Similar to the previous embodiment, the die-casting mold in this embodiment may also include a second shoe last mold without separators, having a shape corresponding to the rubber boot shaft, and adapted to be installed in the inner cavity of the shaft mold to form a complete shaft forming cavity between the wall of the inner cavity of the shaft mold and the outer surface of the second shoe last mold without separators. When the two shaft molds are closed, they combine with the second shoe last mold without separators to form a complete shaft forming cavity.

[0092] Similar to the previous embodiment, the compression molding die in this embodiment may also include a base die. Figure 7 and Figure 8 The diagram shows partial and complete assembly of the outsole mold, guide plate, barrel mold, and last mold with two partitions.

[0093] Figures 10-17 show a combined cylindrical mold, a shoe last mold with dividing elements, etc., according to another embodiment of the present invention.

[0094] In this embodiment, as shown in Figures 10 and 11, the combined cylindrical mold may include three parts: a left cylindrical mold 31, a middle cylindrical mold 33, and a right cylindrical mold 32. These cylindrical molds can be fitted together (i.e., assembled) to form a complete cylindrical mold. The complete cylindrical mold includes a complete cylindrical forming cavity corresponding to the cylindrical body of the rubber boot. These cylindrical molds can also be used with... Figures 12a-12c The shoe last mold 34 with dividing elements shown is assembled to form three separate die-casting cavities. The three separate die-casting cavities correspond to the left rear part, front part, and right rear part of the vulcanized rubber boot shaft, respectively.

[0095] According to this embodiment, the die-casting mold may include two types of shoe last molds: a shoe last mold 34 with a separator element, and a second shoe last mold without a separator element (not shown, see other embodiments).

[0096] like Figure 12a As shown in Figure -c, the dividing element of the shoe last mold 34 according to this embodiment may include a dividing plate 45, a left step portion 41, and a right step portion 42. The dividing plate 45 extends rearward from the shoe last mold, and the left step portion 41 and the right step portion 42 extend vertically on the left and right sides of the shoe last mold, respectively. The dividing element or dividing plate may extend along the entire longitudinal direction (vertical direction in the figure) of the main body portion of the shoe last mold 34. In this embodiment, the dividing plate 45 includes a recessed portion 46 for positioning; in other embodiments, the dividing plate 45 may have a consistent width throughout the longitudinal direction.

[0097] According to this embodiment, the shoe last mold 34 may further include top step portions 43 and 44 for closing the upper part of the intermediate die-casting cavity formed by the shoe last mold 34 and the intermediate cylinder mold 33. The span of the top step portions 43 and 44 can be set as needed. Alternatively, in other embodiments, the same function can be achieved by additionally setting closing features, for example, corresponding features can be set on the glue injection guide plate.

[0098] When performing the corresponding operation, the shoe last mold 34 can first be combined with the intermediate tube mold 33, such as... Figure 14 As shown. The left step portion 41, the right step portion 42, and the top step portions 43 and 44 of the shoe last mold 34 respectively mate with the corresponding parts (e.g., the left and right sides, the top step portion) of the intermediate cylinder mold 33. The step portion provided at the bottom of the shoe last mold 34 mates with the lower step portion of the intermediate cylinder mold 33, thereby forming a closed intermediate die-casting cavity.

[0099] The left cylinder mold 31 and the right cylinder mold 32 can then be combined with the shoe last mold 34 and the middle cylinder mold 33 from both sides, forming a closed left die-casting cavity and a right die-casting cavity between the left cylinder mold 31 and the right cylinder mold 32 and the shoe last mold 34, respectively. Figure 15 This shows the cylinder mold fully closed.

[0100] The presence of the partition plate and steps on the shoe last mold 34 creates three separate chambers: a left chamber, a middle chamber, and a right chamber. These three separate chambers correspond to the shapes of corresponding parts of the rubber boot's body, allowing for the formation of three separate body sections during the die-casting process of the rubber compound. These three separate body sections can be joined in subsequent steps to form the complete vulcanized rubber boot body.

[0101] In addition to other embodiments, the die-casting mold may also include a second last mold without separators. The second last mold without separators may be fitted with a boot lining during manufacturing and moved into the barrel mold after the last mold 34 is removed.

[0102] In a preferred embodiment of the invention, the second shoe last mold can preferably have a shape similar to the barrel of a vulcanized rubber boot, as described in the above embodiments. However, this is not mandatory. Since the barrel mold can be combined to form a complete barrel forming cavity, a second shoe last mold of other shapes can be fitted with a boot lining and placed in the barrel forming cavity. By filling the cavity with pressurized gas, the boot lining can be bonded to the inside of the barrel formed by the rubber material, and a certain pressure can be applied to the barrel.

[0103] In a preferred embodiment, the second shoe last mold is provided with an inflation channel to connect to an external pressurized air source. An air vent can be provided on the surface of the second shoe last mold to inflate the boot lining that fits onto the mold, thereby applying pressure from within the lining to conform it to the boot body and applying a certain pressure to the boot body. In a preferred embodiment, an inflatable airbag or an airtight element with a certain elasticity can be provided between the boot lining and the second shoe last mold to uniformly apply pressure to the boot lining under the action of pressurized gas.

[0104] According to the present invention, the top of the cylinder mold and the bottom of the glue injection guide plate have matching joints, and the glue injection guide plate is adapted to be molded to the top of the cylinder mold through the joints. Figure 16a and 16b A perspective view of a glue-filling guide plate according to an embodiment of the present invention is shown. Figure 16a The side shown can be fitted with the top of the barrel mold and the shoe last mold 34 respectively to inject adhesive. Figure 16b The side shown can be used with an outsole mold to manufacture the sole of a rubber boot.

[0105] like Figure 17 As shown, according to the present invention, the die-casting mold may further include an outsole mold having an outsole injection hole (not shown) and an outsole cavity corresponding to the shape of the rubber boot sole, for die-casting the sole of the rubber boot. The outsole mold has an outsole joining portion and is adapted to be closed to the top of the barrel mold or the top of the injection guide plate via the outsole joining portion when needed.

[0106] In the above embodiment, the left and right stepped portions of the shoe last mold mate with the left and right sides of the intermediate cylinder mold to form an intermediate chamber; the left and right cylinder molds surround the rear middle portion of the shoe last mold to mate with the partition to form a left and right chamber. The shoe last mold and the intermediate cylinder mold also include lower stepped portions that mate with each other to close the lower portion of the intermediate chamber. The left and right cylinder molds include stepped portions that mate with the shoe last mold and the intermediate cylinder mold to form closed left and right chambers. The left and right cylinder molds mate to surround the intermediate cylinder mold and the shoe last mold. The inner surface of the cylinder mold has features suitable for bonding with a rubber surface, such as a relatively high roughness.

[0107] According to another aspect of the present invention, a die-casting molding apparatus for rubber boots is provided, comprising: a die-casting mold according to any of the above embodiments; a high-pressure injection mechanism for pressurizing and injecting a prepared unvulcanized compound into the injection hole of the die-casting mold; a mold moving mechanism for moving various parts of the die-casting mold according to a preset program; and a control mechanism for controlling the operation of the mold moving mechanism and the high-pressure injection mechanism.

[0108] The die-casting equipment may also include heating equipment for heating the uncured rubber compound. For example, after the barrel mold and the second last mold are closed to form a complete barrel from several separate barrel sections, or preferably after the outsole is joined to the barrel, the pre-formed rubber boot is heated (and pressurized by other equipment) for vulcanization.

[0109] The operation of the die-casting mold and die-casting equipment according to the present invention can be found in the following manufacturing method.

[0110] According to another aspect of the present invention, a method for manufacturing vulcanized rubber boots using the above-described die-casting molding equipment is provided, comprising, for example, the following steps:

[0111] 1. Separate the various parts of the barrel mold and move the shoe last mold with separators between the various parts of the barrel mold.

[0112] 2. Close the barrel mold to accommodate the shoe last mold with dividing elements in the appropriate position within the barrel mold; at this point, the mold can be fixed in place using appropriate positioning and clamping devices.

[0113] For example, a shoe last mold with dividing elements is positioned within the barrel mold by engaging its dividing elements or positioning steps with the positioning elements of the barrel mold. Additional fixing devices can be installed in the die-casting equipment to secure the barrel mold and shoe last mold in place. For example, a hydraulic positioning device can be installed. 3. Position and fix the glue injection guide plate to the top of the barrel mold.

[0114] As described above, positioning elements that can engage with each other can be provided at the lower part of the injection guide plate and the top of the cylinder mold. Additional fixing devices can be installed in the die-casting equipment to secure the injection guide plate and cylinder mold in place. For example, a hydraulic positioning device can be provided.

[0115] 4. Inject glue (inject unvulcanized compounded rubber) into the glue injection hole of the glue injection guide plate, and then inject glue into the die casting cavity between the cylinder mold and the shoe last mold with the separator element through the annular glue injection channel of the glue injection guide plate.

[0116] The injection mechanism maintains high pressure to inject the unvulcanized rubber compound. At this time, the annular outlet of the guide plate guides the unvulcanized rubber compound into separate die-casting cavities, helping to reduce the injection pressure and evenly distribute the unvulcanized rubber compound within the die-casting cavities. The unvulcanized rubber compound in the injection mechanism can be appropriately heated to improve its fluidity.

[0117] 5. Open the barrel mold and remove the shoe last mold with the dividing elements.

[0118] At this point, the unvulcanized rubber compound is molded under pressure and temperature in separate die-casting cavities, forming two or more separate parts of the barrel. When the last mold with separators is removed, these parts remain attached to the corresponding parts of the barrel mold. This can be achieved, for example, by selecting the materials of the barrel mold and the last mold with separators, such as having a rougher inner surface on the barrel mold; by using a temperature difference between the last mold and the barrel mold; or by providing features on the inner surface of the barrel mold that facilitate the joining of the barrel parts.

[0119] 6. Place the second shoe last mold (without separators) onto the boot lining and move it between the shaft molds.

[0120] 7. Close the barrel mold to accommodate the second last mold without the separator element in the appropriate position within the barrel mold.

[0121] The positioning of the second shoe last mold within the barrel mold is similar to that of the shoe last mold described above.

[0122] At this point, the shaft mold is closed, and together with the second last mold without separators, pressure is applied to the various parts of the shaft and the boot lining to fit them together.

[0123] Because the boot mold has a modular design, comprising two, three, or more parts, each part can be separated to hold the last mold or a second last mold. These parts can be closed to form a separate die-casting cavity with a last mold with separators, or to form a complete boot mold cavity with a second last mold without separators. When the last mold with separators is removed, the separate parts of the formed rubber boot boot remain on the respective parts of the boot mold. When the second last mold with a boot lining is inserted and the parts of the boot mold are closed, the separate parts of the formed rubber boot boot can engage with each other, and the boot lining can also be engaged within the boot mold.

[0124] An inflation channel can be set inside the second shoe last mold, and high-pressure gas can be provided by an external air pressure source. After the mold is closed, pressurized gas is provided to the surface of the second shoe last mold to press the boot lining on the surface of the second shoe last mold against the inner surface of the rubber boot shaft, promoting mutual adhesion.

[0125] 8. Vulcanize the unvulcanized compound.

[0126] For example, by placing a heating device near the mold, the closed mold is heated, thereby heating the boot body and the second shoe last mold. The rubber boot body is then pressurized with the aforementioned pressurized gas to perform vulcanization. At this point, the various parts of the boot body, along with the boot lining, together form a complete boot body.

[0127] In addition, the following steps may be included before vulcanizing the unvulcanized compound:

[0128] Close the outsole mold (e.g., close the outsole mold to the top of the injection guide plate), and inject adhesive into the outsole injection hole of the outsole mold to form the boot sole; remove the injection guide plate from the barrel mold, and close the outsole mold with the barrel mold (thus the outsole and barrel are joined, and the boot lining is attached to the outsole and barrel). At this time, vulcanize the unvulcanized compound rubber, so that the barrel, outsole, and boot lining are vulcanized as a whole to form a one-piece vulcanized rubber boot.

[0129] The method may further include: removing the outsole mold after vulcanization, opening the barrel mold, and allowing the vulcanized rubber boot to exit the die-casting equipment along with the second last mold without separator elements.

[0130] The method may further include: detaching the vulcanized rubber boot from a second shoe last mold without separating elements using a pneumatic device. For example, if an inflation channel is provided within the second shoe last mold, pressurized gas is supplied directly to the second shoe last mold.

[0131] According to another aspect of the present invention, a die-cast one-piece vulcanized rubber boot is provided, comprising a one-piece die-cast barrel, a sole, and a boot lining, wherein: the barrel has two parting lines at the front and back; or the barrel has three parting lines on the left, right, and rear sides.

[0132] Preferably, the die-cast one-piece rubber boot is manufactured using the method described above.

[0133] When the description mentions terms indicating location such as "left," "middle," "right," "front," "back," "center," "up," and "down," it is merely to clearly indicate the relative position of the components and is not intended to impose any restrictions. Generally speaking, such locations are relative to the location of the shoe last mold.

[0134] The embodiments of the present invention are not limited to those described above. Without departing from the spirit and scope of the present invention, those skilled in the art can make various changes and improvements to the present invention in form and detail, and these are all considered to fall within the protection scope of the present invention.

Claims

1. A die casting mold for vulcanized rubber boots, comprising: a combined barrel mold having an inner cavity corresponding to a barrel of a rubber boot; a last mold with a partitioning element having a main body substantially corresponding to a shape of the barrel of the rubber boot, and two or more partitioning elements provided on the main body, the last mold being adapted to be mounted into the inner cavity of the barrel mold to form a die casting cavity between a wall of the inner cavity of the barrel mold and an outer surface of the last mold, the die casting cavity being partitioned by the last mold and the barrel mold into two or more portions; and a runner plate adapted to be mounted on top of the barrel mold to guide injection of an unvulcanized compound, the runner plate comprising a plate body, wherein the plate body is provided with: a runner hole adapted to be connected with an external injection head to inject the unvulcanized compound; and an annular runner channel for guiding the externally injected unvulcanized compound into the die casting cavity in an annular distribution.

2. The die casting mold according to claim 1, wherein The partitioning element of the last mold comprises two partitioning plates respectively extending from the last mold to a front side and a rear side.

3. The die casting mold according to claim 2, wherein When the last mold is mounted into the barrel mold, the two partitioning plates partition the die casting cavity into a left chamber and a right chamber.

4. The die casting mold according to claim 3, wherein the barrel mold comprises a left barrel mold and a right barrel mold which are mountable to each other; and the two partitioning plates partition the left chamber and the right chamber corresponding to the left barrel mold and the right barrel mold.

5. The die casting mold according to claim 1, wherein The partitioning element of the last mold comprises three partitioning plates, a first partitioning plate extending from the last mold to a rear side, and a second partitioning plate and a third partitioning plate respectively extending from the last mold to a left side and a right side.

6. The die casting mold according to claim 5, wherein When the last mold is mounted into the barrel mold, the three partitioning plates partition the die casting cavity into three chambers: a middle chamber, a left chamber and a right chamber.

7. The die casting mold according to claim 6, wherein the barrel mold comprises three barrel mold portions mountable to each other; and the three partitioning plates partition the middle chamber, the left chamber and the right chamber corresponding to the three barrel mold portions, respectively.

8. The die casting mold according to claim 1, wherein The partitioning element of the last mold comprises a partitioning plate extending from the last mold to a rear side, and a left step portion and a right step portion respectively extending in a vertical direction at a left side and a right side of the last mold.

9. The die casting mold according to claim 8, wherein when the last mold is mounted into the barrel mold, the partitioning plate, the left step portion and the right step portion partition the die casting cavity into a middle chamber, a left chamber and a right chamber.

10. The die casting mold according to claim 9, wherein the barrel mold comprises a middle barrel mold, a left barrel mold and a right barrel mold mountable to each other; and the partitioning plate, the left step portion and the right step portion partition the middle chamber, the left chamber and the right chamber corresponding to the middle barrel mold, the left barrel mold and the right barrel mold, respectively.

11. The die casting mold of claim 10, the left and right step portions of the last mold cooperate with the left and right sides of the middle barrel mold to form a middle cavity; the left and right barrel molds enclose the middle back portion of the last mold to cooperate with the partition to form left and right cavities.

12. The die casting mold of any one of claims 9-11, the last mold further comprises a top step portion to close the upper portion of the middle cavity.

13. The die casting mold of claim 12, the last mold and the middle barrel mold further comprise lower step portions that cooperate with each other to close the lower portion of the middle cavity.

14. The die casting mold of any one of claims 10 or 11, the left and right barrel molds comprise step portions that cooperate with the last mold and the middle barrel mold to form closed left and right cavities.

15. The die casting mold of any one of claims 10 or 11, the left and right barrel molds cooperate to enclose the middle barrel mold and the last mold.

16. The die casting mold of any one of claims 1-11, the inner surface of the barrel mold has features adapted to bond with a rubber surface.

17. The die casting mold of any one of claims 1-11, further comprising: a second last mold without a partition element adapted to be installed into the inner cavity of the barrel mold.

18. The die casting mold of claim 17, the second last mold has a shape corresponding to the barrel of a rubber boot to form a barrel forming cavity between the wall of the inner cavity of the barrel mold and the outer surface of the last mold without a partition.

19. The die casting mold of claim 17, the second last mold has a shape different from the barrel of a rubber boot.

20. The die casting mold of claim 18 or 19, the second last mold has an inflation channel adapted to connect to an external pressurized air source and air vents disposed on the surface.

21. The die casting mold of claim 20, the second last mold has an air bladder disposed thereon.

22. The die casting mold of any one of claims 1-11, the top of the barrel mold and the bottom of the injection guide plate have mating bonding sites that cooperate with each other, the injection guide plate is adapted to be clamped to the top of the barrel mold through the mating bonding sites.

23. The die casting mold of any one of claims 1-11, further comprising: an outsole mold having an outsole injection hole and an outsole mold cavity corresponding to the shape of the outsole of a rubber boot for die casting the outsole of a rubber boot; the outsole mold has an outsole bonding site and is adapted to be clamped to the top of the barrel mold and the top of the injection guide plate through the outsole bonding site.

24. The die casting mold of any one of claims 1-11, wherein the plate body is further provided with a distribution chamber, the distribution chamber is connected to the injection hole through an injection channel and connected to the annular injection channel through a guide channel.

25. The die casting mold of claim 24, wherein the flow guide passages are a plurality of passages each connecting the distribution chamber to the annular injection channel.

26. The die casting mold of claim 24, wherein the flow guide passages are four passages spaced around the distribution chamber.

27. The die casting mold of claim 24, wherein the injection port is provided on one side of the plate body and the distribution chamber is provided in the middle of the plate body.

28. The die casting mold of any one of claims 1 to 11, wherein the annular injection channel is an annular outlet formed at one end face of the plate body.

29. The die casting mold of claim 28, wherein the annular outlet has a shape corresponding to the annular shape of the bottom of the rubber boot shaft.

30. A die casting apparatus for a rubber boot, comprising: a die casting mold according to any one of claims 1 to 29; a high pressure injection mechanism for pressurizing and injecting prepared uncured rubber compound into the injection port of the die casting mold; a mold moving mechanism for moving each part of the die casting mold according to a predetermined program; and a control mechanism for controlling the operation of the mold moving mechanism and the high pressure injection mechanism.

31. The die casting apparatus of claim 30, further comprising a heating apparatus for heating the uncured rubber compound.

32. A method of manufacturing a vulcanized rubber boot using the die casting apparatus of claim 30 or 31, comprising: moving a last mold with a separating element between separate shaft molds; closing the shaft molds to accommodate the last mold in place in the shaft molds; positioning and fixing an injection guide plate on top of the shaft molds; injecting rubber compound into the injection port of the injection guide plate and thereby injecting the uncured rubber compound through the annular injection channel of the injection guide plate into the die casting cavity between the shaft molds and the last mold; opening the shaft molds and removing the last mold; sleeving a second last mold without a separating element with a bootie and moving it between the shaft molds; closing the shaft molds to accommodate the second last mold in place in the shaft molds; vulcanizing the uncured rubber compound to form the shaft of the rubber boot. closing a sole mold to the upper part of the injection guide plate and injecting rubber compound into the sole injection port of the sole mold to form a sole; removing the injection guide plate from the shaft molds and closing the sole mold with the shaft molds; 33. The method of claim 32, further comprising the step of: injecting pressurized air into the interior of the bootie through the air filling channel in the second last mold to press the bootie against the inner surface of the shaft and to press the shaft, while heating the shaft and the second last mold by the heating apparatus, so that the uncured rubber compound is vulcanized and the shaft and the sole are integrally vulcanized to form an integrated vulcanized rubber boot. providing an air bag between the bootie and the second last mold to uniformly press the bootie.

34. The method of claim 33, further comprising: the second last mold has a shape different from that of the rubber boot.

35. The method of claim 33 or 34, further comprising:

36. The method of claim 33, further comprising: after vulcanization, removing the sole mold, opening the shaft molds, and removing the vulcanized rubber boot with the second last mold from the die casting apparatus. ​ 37. The method of claim 36, further comprising: disengaging the vulcanized rubber boot from the second last by means of a pneumatic device.

38. An integral vulcanized rubber boot formed by the method of claims 32-37, comprising an integrally formed shaft, sole, and bootie.

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